Antioxidant Activity of Eight Hydrosols from Morocco

Essential oils from aromatic and medicinal plants have received particular attention as potential natural agents for food preservation and medicine. Nevertheless, much less attention has been given to the components which remain dissolved in the distillation water. To this fraction which is quite fragrant and strongly flavoured with values of pH ranging from 4.5-5.5 is called hydrosol. The antioxidant activity of hydrosols produced by an enterprise from Morocco from eight aromatic species (Pelargonium graveolens, Artemisia herba-alba, Cupressus atlantica, Ocimum basilicum, Juniperus phoenicea, Pinus pinaster, Marrubium vulgare and Hyssopus officinalis) was evaluated. Several methods were used: Thiobarbituric acid Reactive Species (TBARS), Trolox Equivalent Antioxidant Capacity (TEAC), hydroxyl and superoxide scavenging abilities. The results showed that in TBARS and superoxide scavenging ability, H. officinalis hydrosol revealed to be the most effective (IC50 = 136 mg mL-1 and IC50 = 2 mg mL-1, respectively). In the TEAC assay, M. vulgare was the most effective (IC50 = 72 mg mL-1), although H. officinalis also presented a good activity ((IC50 = 87 mg mL-1). A. herba-alba hydrosol presented the best capacity for scavenging hydroxyl free radical (IC50 = 95 mg mL-1).